1. 2.5; 8-26 Even
8. Hypothesis: the measure of and angle is 60 Conclusion: the angle is acute
10. If a bird is an eagle, then it east fish.
12. If two angles form a linear pair, then they are supplementary.
14. The intersection of the planes is a line.
16. Argument 1 is correct. Why?
18. If the stereo is on, then the neighbors will complain.
20. If you want a great selection of used cars, then you should come and see Bargain Bob’s Used Cars.
22. Must not
24. If you tell the truth, then you don’t have to remember anything.
26. If one is lucky, then a solitary fantasy can totally transform one million realities.

2. 2.6 Properties of Equality and Congruence
Goal:
Use Properties of Equality and Congruence.

3. Properties of Equality and Congruence
Reflexive Property
Equality
Congruence

4. Properties of Equality and Congruence
Symmetric Property
Equality If , then
If , then
Congruence If , then
If , then

5. Properties of Equality and Congruence
Transitive Property
Equality If and , then
If and , then
Congruence If and , then
If and , then

6. Name Properties of Equality and Congruence
Name the property that the statement illustrates.
Symmetric Property of Congruence
Reflexive Property of Equality
Transitive Property of Congruence

7. Use Properties of EqualityM N P Q
MN = NP Definition of midpoint
NP = PQ Definition of midpoint
MN = PQ Transitive Property of Equality

8. Properties of Equality
Addition Property
Adding the same number to each side of an equation produces an equivalent equation.
x – 3 = 7
x – = 7 + 3
Subtraction Property
Subtracting the same number from each side of an equation produces an equivalent equation.
y +5 = 11
y =11 - 5

9. Properties of Equality
Multiplication Property
Multiplying the same number to each side of an equation produces an equivalent equation.
Division Property
Dividing each side of an equation by the same number produces an equivalent equation.
8x = 16
8x/8 = 16/8

10. Properties of Equality
Substitution Property
Substituting a number for a variable in an equation produces an equivalent equation.
x = 7
2x + 4 =2(7) + 4

11. Justify the Congruent Supplements Theorem1 2 3
Definition of Supplementary angles
Substitution Property of Equality
Subtraction Property of Equality
Definition of congruent angles

12. Homework
2.6 pg. 91
10-20 All